AMD Radeon HD 8790M: Next-Gen Mobile Mainstream Graphics Preview

AMD sent over some of its lab gear: an interposer card and two PCI Express-based boards with MXM modules...one of which hosted its upcoming Radeon HD 8790M GPU. At long last, the GCN architecture is hitting mainstream notebooks in its 28 nm glory.

An Experiment, At Best, But One The Shows Promise

We love spending time in the lab. Running benchmark results is what helps us draw conclusions, which in turn form the basis for our recommendations. It feels a little odd, then, that we cannot draw many conclusions from today's preview, nor make any recommendations, even though we've actually spent a substantial amount of time testing. This was really an experiment in the truest sense, designed to mitigate certain factors (like dissimilar platforms), while at the same time introducing new variables (like the unrealistic openness of a desktop for mobile benchmarking).

But here's what we know. Although the Radeon HD 8000M series is named for what gaming enthusiasts might expect to be a next-gen architecture, it centers on the Graphics Core Next design found in AMD's desktop Radeon HD 7000 and mobile Radeon HD 7800M/7900M GPUs. Naming confusion aside, that's still good news in the mainstream notebook segment, where 28 nm manufacturing helps improve efficiency. When every frame per second matters, squeezing out more performance per watt of power consumption means the difference between playable settings and a slide show. Our benchmarks show this.

We also know that the Radeon HD 8500M, 8600M, 8700M, and 8800M families are not yet shipping in any OEM notebooks. As a result, our testing involved putting the Radeon HD 8790M and its corresponding module into a PCI Express interposer card and benchmarking it on a desktop platform. Although AMD is waiting for CES 2013 to talk power figures, it is willing to go on the record and say the Radeon HD 8700M-series parts can run in the same systems in which you'd typically find a Radeon HD 7670M. We do not know whether the old and new GPUs will be priced similarly, but thermal compatibility was our biggest concern before drawing any sort of comparison, above all else.

Pre-Production Radeon HD 8790M MXM Module

It's not clear why real-world applications like WinZip 17 and Photoshop CS6 wouldn't cooperate, but we're chalking that up to the early nature of our hardware and drivers, along with the non-standard testing setup we used to get our benchmark results.

Great Graphics And Small Form Factors: Mutually Exclusive No More?

If there is one weakness that keeps us as enthusiasts and gamers from getting more excited about Intel's Ultrabooks, it's the graphics situation. Currently, the thinnest and lightest designs are forced to rely on Intel's HD Graphics engine, which is woefully underpowered for most of the titles folks like us get excited about. Understandably, then, when Acer launched its Timeline Ultra M3 with GeForce GT 640M graphics back in March, our heads turned. Now we're hoping that AMD's 28 nm, GCN-enabled mobile GPUs are able to compete in that same space, giving road warriors Ultrabook more options able to game.

Of course, Nvidia has a substantial head start. But we've now seen that AMD's Radeon HD 8790M comes armed with enough horsepower to play Hitman, Far Cry 3, Skyrim, WoW, Battlefield 3, and Call of Duty, sometimes even with the details cranked all the way up. AMD's GCN architecture also has a huge advantage over Nvidia's Kepler in compute-optimized titles. As software developers like Corel and Adobe continue leveraging OpenCL, we'll see more and more reason to need a strong GPU for tasks other than games. That's especially true in small notebooks, which often sport weaker 17, 25, and 35 W dual-core CPUs.

We're keeping our eye to CES in a couple of weeks, when AMD will hopefully have more to say about some of the companies looking to adopt its Radeon HD 8000Ms and what their designs will look like!

Wow, can't say I expected to see any 8000 series/700 series benchmarks for at least a few months. Looks prettyimpressive for a mobile GPU, can't wait to see what the high end mobile and desktop cards can do.

A Bad DaySometimes I wonder why instead of CFing or SLIing two high end mobile GPUs, a desktop GPU would've achieved the same performance but without the stuttering or driver issues. And if thermal management is an issue, then the desktop GPUs could always be undervolted (but of course more expensive because of the extra step).
If you look, there is only one chip (shown on this page) which means it is not being CrossFired. I agree that 8780M would be a better name than 8790M. Andrew Ku, maybe on the front page you can clarify this?

About using desktop parts, it is my understanding that they sometimes do exactly that. Take the 7970M, which as far as I can tell, is an 78XX part (I forget which one) except the mobile chip has MUCH higher binning than the desktop 78XX.